An arithmetic sequence has first term a and common difference d. The sum of the first 20

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An arithmetic sequence has first term a and common difference d. The sum of the first 20 terms is seven times the sum of the first five terms.
a. Find d in terms of a.

b. Find the 65th term in terms of a.

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Cambridge International AS And A Level Mathematics Pure Mathematics 1 Coursebook

ISBN: 9781108407144

1st Edition

Authors: Sue Pemberton, Julian Gilbey

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Question Posted: Mar 10, 2023 05:52 AM

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An arithmetic sequence has first term a and common difference d. The sum of the first 20

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a Let S20 be the sum of the first 20 terms and S5 ...View the full answer

Cambridge International AS And A Level Mathematics Pure Mathematics 1 Coursebook

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